US5347075A - Mutagenesis testing using transgenic non-human animals carrying test DNA sequences - Google Patents

Mutagenesis testing using transgenic non-human animals carrying test DNA sequences Download PDF

Info

Publication number
US5347075A
US5347075A US07/711,332 US71133291A US5347075A US 5347075 A US5347075 A US 5347075A US 71133291 A US71133291 A US 71133291A US 5347075 A US5347075 A US 5347075A
Authority
US
United States
Prior art keywords
test
dna
test dna
dna sequence
sequence
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US07/711,332
Inventor
Joseph A. Sorge
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Agilent Technologies Inc
Original Assignee
Stratagene California
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Stratagene California filed Critical Stratagene California
Priority to US07/711,332 priority Critical patent/US5347075A/en
Assigned to STRATAGENE reassignment STRATAGENE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: SORGE, JOSEPH A.
Application granted granted Critical
Publication of US5347075A publication Critical patent/US5347075A/en
Assigned to UNION BANK reassignment UNION BANK SECURITY AGREEMENT Assignors: STRATAGENE
Assigned to UNION BANK OF CALIFORNIA, N.A. reassignment UNION BANK OF CALIFORNIA, N.A. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: UNION BANK
Assigned to STRATAGENE CALIFORNIA reassignment STRATAGENE CALIFORNIA CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: STRATAGENE
Assigned to STRATAGENE reassignment STRATAGENE ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: UNION BANK OF CALIFORNIA, N.A.
Assigned to AGILENT TECHNOLOGIES, INC. reassignment AGILENT TECHNOLOGIES, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: STRATAGENE CALIFORNIA
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N15/00Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
    • C12N15/09Recombinant DNA-technology
    • C12N15/63Introduction of foreign genetic material using vectors; Vectors; Use of hosts therefor; Regulation of expression
    • C12N15/79Vectors or expression systems specially adapted for eukaryotic hosts
    • C12N15/85Vectors or expression systems specially adapted for eukaryotic hosts for animal cells
    • C12N15/8509Vectors or expression systems specially adapted for eukaryotic hosts for animal cells for producing genetically modified animals, e.g. transgenic
    • AHUMAN NECESSITIES
    • A01AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01KANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K67/00Rearing or breeding animals, not otherwise provided for; New or modified breeds of animals
    • A01K67/027New or modified breeds of vertebrates
    • A01K67/0275Genetically modified vertebrates, e.g. transgenic
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12QMEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
    • C12Q1/00Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
    • C12Q1/02Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving viable microorganisms
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12QMEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
    • C12Q1/00Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
    • C12Q1/02Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving viable microorganisms
    • C12Q1/18Testing for antimicrobial activity of a material
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12QMEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
    • C12Q1/00Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
    • C12Q1/68Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving nucleic acids
    • C12Q1/6897Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving nucleic acids involving reporter genes operably linked to promoters
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/48Biological material, e.g. blood, urine; Haemocytometers
    • G01N33/50Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
    • G01N33/5005Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving human or animal cells
    • G01N33/5008Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving human or animal cells for testing or evaluating the effect of chemical or biological compounds, e.g. drugs, cosmetics
    • G01N33/5014Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving human or animal cells for testing or evaluating the effect of chemical or biological compounds, e.g. drugs, cosmetics for testing toxicity
    • G01N33/5017Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving human or animal cells for testing or evaluating the effect of chemical or biological compounds, e.g. drugs, cosmetics for testing toxicity for testing neoplastic activity
    • AHUMAN NECESSITIES
    • A01AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01KANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K2217/00Genetically modified animals
    • A01K2217/05Animals comprising random inserted nucleic acids (transgenic)
    • AHUMAN NECESSITIES
    • A01AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01KANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K2227/00Animals characterised by species
    • A01K2227/10Mammal
    • A01K2227/105Murine
    • AHUMAN NECESSITIES
    • A01AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01KANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K2267/00Animals characterised by purpose
    • A01K2267/03Animal model, e.g. for test or diseases
    • A01K2267/0393Animal model comprising a reporter system for screening tests

Definitions

  • This invention pertains to tests for monitoring mutagenic agents and to transgenic animals. More specifically, the invention relates to genotypic changes in live animals that are monitored by the creation and use of transgenic non-human animals carrying marker DNA sequences that can be quickly recovered and examined for mutations.
  • Eukaryotic cell lines have also been used to detect mutations.
  • Glazer et al. Detection and Analysis of UV-induced Mutations in Mammalian Cell DNA using Lambda Phage Shuttle Vector., Proc. Natl. Acad. Sci. USA 83:1041-1044 (1986).
  • a target test gene the amber suppressor tyrosine tRNA gene of E. coli in a bacteriophage shuttle vector, was integrated into a genomic host mammalian cell line by DNA transfection. After exposing the host cell line to putative mutagenic agents, test genes were re-isolated, propagated in bacteria, and analyzed for mutations. Because the host is only a mammalian cell line and not a live animal, the test is incapable of accurately monitoring mutagenic metabolites of the agent being tested that are only produced at the appropriate concentrations by differentiated cells or the tissue of live animals.
  • test genes and large scale screening assays are not available for live animal studies. Short of relying on longterm animal studies that detect phenotypic changes that require a long time to be identifiable, such as tumors, organ failure, etc., current tests do not provide a means for monitoring organ-specific mutations of DNA. Hence, there exists a need for a system that places a test DNA sequence within an animal and is subsequently assayed on a large scale for mutations. There also exists a need for a test that detects mutations caused by chemical metabolites of the agent being tested. To be most effective the system needs to be capable of monitoring small genetic changes in as many tissues of an animal and as easily, rapidly, and inexpensively as possible.
  • the present invention produces a test that satisfies these needs.
  • the test is a sensitive screen for the mutagenicity of all agents.
  • the test not only monitors the mutagenic effects of the agent being screened it also monitors the mutagenic effects of all metabolites that occur in animal tissues of the agent being tested. It permits the identification of the nature of the mutation: e.g., DNA transition, transversion, deletion, or a point or frameshift mutation.
  • the test is rapid and it is inexpensive relative to other tests. And, it will spot a potential mutagen rapidly before other more expensive tests can be completed.
  • FIG. 1 illustrates the sequence of process steps for performing the invention.
  • FIG. 2 illustrates an alternative method for recovering the transgenic test DNA sequence.
  • the present invention involves the introduction of at least one copy of at least one target DNA sequence into the cells of a non-human animal that is then bred to produce test animals. This test transgenic animal is then exposed to an agent that is suspected to be mutagenic. The target test DNA sequence is subsequently recovered from individual tissues of the transgenic animal and is transferred into a microorganism, where it can be assayed for mutations, allowing rapid examination of multiple tissue specific genetic mutations.
  • any animal suitable for mutagenic testing may be used as the starting organism.
  • single cell animal embryos can be harvested, although there may be other cells facilitating the uptake and ultimate ubiquitous presence of the marker DNA in every cell of a differentiated animal.
  • a test DNA sequence must be prepared for insertion into the animal. Any number or variety of sequences coding for a phenotype or genotype that is easily detectable upon mutation may be used.
  • a vector capable of facilitating the recovery of the test DNA sequence from the host animal cells, and capable of allowing autonomous replication and expression of the sequence in the anticipated bacterial host may be used as a carrier for the target test DNA sequence.
  • the construct for such a vector and insert should contain, at least, regions that allow insertion into and excision from the animal host genome, and regions that allow autonomous replication in the bacterial host cell, as well as regions that allow expression and assay of the test DNA sequence. If integration into the host genome is not required, desired regions that allow for replication of the test DNA sequence in the animal host cells should be present.
  • a next step involves transforming the host animal with the test DNA sequence, so as to provide the stable presence of the test sequence throughout cells of the differentiated animal.
  • this involves the integration of the test DNA sequence into the animal host genome, although methods that allow the test sequence to be stably and heritably present through the use of autonomously replicating vectors may also be useful.
  • the vector containing the test DNA sequence must be physically introduced into the animal. At the cellular level, this may be accomplished using the techniques of microinjection, electroporation, dielectrophoresis or various chemically mediated transformation techniques, all of which are well known in the art.
  • other techniques may be necessary.
  • the transgenic cells must be allowed to differentiate into a whole organism. This may be done, for example, by embryo implantation into pseudopregnant females, or by other techniques allowing maturation of transgenic embryos. Once such maturation and differentiation has occurred, the animal is assayed for the presence of the test DNA sequence. Typically this involves removing small portions of tissue from the animal and using DNA hybridization assay techniques to detect the presence of the test DNA sequence.
  • the animal may be bred and its offspring that carry the transgenic DNA sequence may be used for studies of mutagenesis.
  • the test animal is exposed to the agent or substance in question under appropriate conditions. Such conditions will depend, for example, on the nature of the agent or substance, the purpose of the mutagenesis study and the type of data desired.
  • tissues are removed from the test animal. Because the test DNA sequence is present in essentially all tissues, the tissue type tested is not limited by the process of insertion of the test sequence. Any desired tissue may be removed. Genomic DNA is purified from the tissue.
  • the target test DNA sequence which is integrated is rescued from the total genomic DNA of the host. This may be accomplished by excising it from the host genome or by any procedures allowing separation by size, weight or charge density. The method of rescue is dependent upon whether test DNA sequence is inserted into the genome, and whether flanking regions allow for excision, or whether the test DNA sequence is part of an autonomously replicating element allowing for separation techniques.
  • test DNA sequences are then transferred into and expressed by microorganisms appropriate for large scale screening techniques. Typically this involves excising the test DNA sequence vector from the genomic DNA by packaging the test DNA sequence with bacteriophage packaging techniques, but it may require ligating the test DNA sequence into an appropriate vector or merely require direct transformation into a microorganism.
  • the microorganisms containing the test DNA sequence vector are then grown on indicator plates or in selective media. Those organisms having a phenotype indicating mutation of the test DNA sequence may be considered to contain a mutated test DNA sequence.
  • the ratio of those organisms expressing mutated phenotype of test sequences to the total number of organisms containing the test DNA sequence is a measure of the mutagenicity of the agent and metabolites of it present in the tested tissue.
  • mice were used as the test animal. Single cell mouse embryos were harvested from female mice that were impregnated the evening before. The embryos were treated with hyaluronidase and briefly cultured in M16 medium. The embryos were transferred to M2 medium on a microscope glass depression slide. The embryos were observed with a 40 X objective and a 10 X eyepiece using a Nikon Diaphot microscope equipped with Hoffman optics. The embryos were held in place with a holding pipet that had been rounded with a microforge. The positions of both the holding pipets and the injection pipets were controlled with micromanipulators. DNA as described below was loaded in the injection pipet at a concentration of 1 to 10 micrograms per milliliter. Approximately one picoliter, as judged by a refractile change of the pronucleus, of DNA solution was injected into the male pronucleus.
  • the embryos were transferred to M16 medium and incubated at 37° C. in a 5% CO 2 atmosphere for one to two hours. Lysed embryos were discarded and embryos that appeared normal were transferred to one of the fallopian tubes of pseudopregnant foster mothers. The transfers were performed under a dissecting microscope using general anesthesia (avertin).
  • mice After birth, newborn mice were kept with their foster mothers for 2 weeks, at which point they were then weaned and screened for DNA integration. A 2 cm portion of the tail was removed and homogenized in 2 ml of a solution of 0.1M NaCl, 50 mM Tris-HCl, pH 7.5, 1 mM EDTA for short duration, but long enough to disrupt cell and nuclear membranes. The homogenized tissue was treated with 50 U/ml RNaseA and 0.1% SDS for 15 minutes at 37° C. The mixture was exposed to Proteinase K digestion for 3 hours at 55° C. followed by three extractions with phenol/chloroform. DNA was then precipitated by the addition of ethanol.
  • the filter with transferred DNA was hybridized overnight with 32 P labeled lambda DNA prepared, according to standard procedures, by the method of nick translation. Maniatis, supra. Following this overnight hybridization, the filter was washed in 0.1 ⁇ SSC, 0.1% SDS at 50° C. and Kodak XAR film was exposed to it in order to identify lambda DNA present within the mouse genome. Lambda DNA, used as standards, that had been electrophoresed alongside the mouse genomic DNA were compared in intensity to the transgenic mouse DNA hybridized to the 32 P labeled lambda DNA to estimate copy number. Numerous transgenic animals have been produced and identified by this technique and most of them transmit the integrated DNA to their offspring, demonstrating germ line integration.
  • the test sequence DNA can, theoretically, contain any number or variety of genes or other identifiable test DNA sequences.
  • an E. coli bacteriophage lambda genome has been engineered to carry a beta-galactosidase test DNA sequence.
  • the genotype of the modified lambda genome L2B is lac5 delta (shindIII lambda 2°-3°) srI lambda 3°-5° cI857 sXhl lambda 1° sScII lambda 4°.
  • this lambda DNA was diluted to a concentration of 10 micrograms per milliliter and the cos ends were annealed and ligated under conditions predominantly forming circular lambda phage monomers.
  • mice were tested for the presence of the test DNA sequence by the tail-blotting procedure. Hogan, et al., Manipulating the Mouse Embroyo: A Laboratory Manual, pp. 174-183 (Cold Spring Harbor Laboratory, 1986). Several of the newborns were found to carry the test DNA sequence in DNA isolated from their tails. Eight weeks after birth these transgenic mice were mated and their progeny were examined for the test DNA sequence. Approximately 50% of the resulting offspring carried the test DNA sequence, demonstrating that the original transgenic mice carried the test DNA sequence in their germ line and that this sequence was inherited normally. While transgenic lines having approximately one copy of the test DNA sequence per cell can be obtained, lines having at least about 5-10 copies per cell are preferred. This is believed to make the rescue procedure more efficient.
  • the target vector lambda L2B can be used initially to establish background mutagenesis rates within transgenic mouse strains.
  • a variation of L2B may be constructed that also contains a plasmid sequence that can be readily excised from the lambda phage and contains the Lac I gene.
  • This variation may have two advantages. First, mutations will appear as blue plaques on a white background in the presence of X-gal (5-bromo-4-chloro-3-indolyl- ⁇ -D-galactopyranoside) without IPTG (isopropyl ⁇ -D-thiogalactopyranoside). This should aid in the identification of mutations. Second, the blue plaques will represent Lac I mutations which may be isolated and rapidly assessed.
  • the test DNA sequence can be found within the genomic DNA. Since the test DNA sequence is contained within a lambda phage genome, it can be excised away from the remainder of the genomic DNA by using a lambda phage packaging extract. Approximately 10 micrograms of genomic DNA (isolated as described above) is added to 100 microliters of lambda phage packaging extract (Gigapack Gold, Stratagene Cloning Systems, San Diego, Calif.) and incubated for 2 hours at 23° C. The reaction is then diluted with 5000 microliters of SM (100 mM NaCl, 8 mM MgSO 4 7H 2 O, 50 mM.
  • SM 100 mM NaCl, 8 mM MgSO 4 7H 2 O, 50 mM.
  • Tris pH 7.5, 0.01% gelatin
  • the reaction mixture is then added to 2 ⁇ 10 9 ⁇ -galactosidase deficient E. coli that have been grown in the presence of 0.2% maltose and 10 mM MgCl 2 . After incubating at 37° C.
  • the phage plaques turn blue if the beta-galactosidase sequence within the lambda genome has not mutated.
  • a white plaque on the petri dish is evidence that a mutation in the beta-galactosidase sequence has, for example, altered the reading fram, altered essential codons, or have created stop codons in the sequence.
  • These white plaques will be scored as positive for mutations and they can be plaque purified and saved for further analysis. The ratio of white to blue plaques minus background will indicate the mutagenesis potency of the agent being tested when compared with DNA extracted from mice that have not been treated with potentially mutagenic agents.
  • rescue of the marker DNA sequence is possible because it is contained within a lambda bacteriophage genome.
  • the entire lambda bacteriophage genome is excised from the mouse chromosome by the in vitro packaging extract.
  • the packaging extract recognizes the cos sites of the integrated lambda DNA and packages the sequences between the cos sites into lambda phage particles, as shown in FIG. 1.
  • test DNA sequence rescue efficiency can be influenced by the state of CpG methylation in the mouse chromosome. Highly methylated DNA may not be efficiently excised by lambda packaging extract, presumably because of inhibition of cleavage at the cos sites. It is anticipated that this can be alleviated by placing transcriptional enhancers, promoters and/or other regions of the DNA which inhibit methylation near the cos site to reduce CpG methylation.
  • the drug 5'-azacytidine can also be used to reduce the level of DNA methylation in the target cells prior to DNA purification and rescue. Jaenisch, R., et al., Proc. Natl. Acad. Sci. USA 82:1451-1455 (1985).
  • fibroblast cell lines are obtained from organisms containing the test DNA sequence of interest. Adams, R. L. P., Cell Culture for Biochemists, pages 68-83 (1980 Elselvier/North Holland Biomedical Press). The cells are exposed in vitro at 37° C., with 50 ⁇ m 5'azacytidine supplementing the culture medium. Upon DNA replication, the daughter DNA loses its CgG methylation, which eliminates the methylation of cos sites in the target vector, where the target vector is a lambda phage. The DNA from these fibroblasts is then exposed to in vitro packaging extract, as previously described.
  • organisms containing the test DNA sequence can be directly injected with a 1 mg/ml solution of 5'-azacytidine in 0.15M NaCl. This is done over a period of at least 4 days, with a total of 400 ⁇ g administered. Jaenisch, supra. After this treatment, DNA can be extracted from various tissues and packaged as before.
  • test DNA sequence or gene can be inserted between lambda cos sites.
  • the in vitro packaging extract would still excise the DNA between the cos sites and insert it into a lambda phage particle.
  • a variety of recombinant lambda genomes or cosmids may be used for this excision event.
  • the embodiment described above utilizes the E. coli beta-galactosidase gene as a test DNA sequence, which allows phenotypes that are positive and negative for mutation to be observed.
  • Other potential test DNA sequences include (but are not limited to): the lac I repressor, the cl repressor, any antibiotic resistance gene sequence (ampicillin, kanamycin, tetracycline, neomycin, chloroamphenicol, etc.), the lambda red and gam gene sequences, a thymidine kinase gene sequence, a xanthine-guanine phosphoribosyl transferase gene sequence, sequences that code for restriction enzymes or methylation enzymes, a gene sequence that codes for luciferase, and/or a tRNA stop codon or frameshift suppressor gene sequence.
  • test sequence(s) By bracketing the test DNA sequence(s) with convenient restriction sites, as shown in FIG. 2, the test sequence(s) can be separated away from the mouse DNA with restriction enzymes and subsequently ligated with lambda or cosmid vectors which contain cos sites. Background can be reduced in such a system by including with the test DNA sequences a sequence that is necessary for lambda phage replication, which is then cloned with the test DNA sequence into a lambda genome deficient or defective in that sequence.

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Zoology (AREA)
  • Genetics & Genomics (AREA)
  • Wood Science & Technology (AREA)
  • Biotechnology (AREA)
  • General Health & Medical Sciences (AREA)
  • Molecular Biology (AREA)
  • Immunology (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Microbiology (AREA)
  • Biochemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Biomedical Technology (AREA)
  • Biophysics (AREA)
  • Analytical Chemistry (AREA)
  • Toxicology (AREA)
  • Hematology (AREA)
  • Veterinary Medicine (AREA)
  • Environmental Sciences (AREA)
  • Urology & Nephrology (AREA)
  • Animal Behavior & Ethology (AREA)
  • Medicinal Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Pathology (AREA)
  • Food Science & Technology (AREA)
  • Cell Biology (AREA)
  • Animal Husbandry (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Tropical Medicine & Parasitology (AREA)
  • Plant Pathology (AREA)
  • Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
  • Micro-Organisms Or Cultivation Processes Thereof (AREA)
  • Investigating Or Analysing Biological Materials (AREA)

Abstract

An assay for monitoring and assessing the mutagenic potential of agents which involves creating transgenic non-human animals carrying a test DNA sequence or sequences that can be quickly recovered and examined for mutations following exposure to one or more suspected mutagenic agents.

Description

This is a continuation of application Ser. No. 07/045,037, filed May 1, 1987, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains to tests for monitoring mutagenic agents and to transgenic animals. More specifically, the invention relates to genotypic changes in live animals that are monitored by the creation and use of transgenic non-human animals carrying marker DNA sequences that can be quickly recovered and examined for mutations.
2. Description of Related Art
Various agents, such as radiation, ultraviolet light, synthetic chemicals, natural substances, and aberrations in genetic replication and repair can produce mutations in DNA. Whenever a new chemical, drug, or food additive, for example, is to be taken from the laboratory to the marketplace, it must be tested for its toxicity and cancer-causing potential. Existing tests that assess the mutagenic potential of substances focus either on alterations of DNA in cultured cells or alterations in the health of test animals. Unfortunately, few tests that monitor alterations in DNA actually expose live animals to the agent to be tested. This is because it is very difficult to rapidly monitor small alterations in the genetic code simultaneously in many different organs. Tests to detect these mutations must be very sensitive. They must be able to detect a single mutation amongst millions of normal genetic units. The difficulty of this task currently makes this approach prohibitively expensive for live animal studies. Therefore, most current live animal toxicity tests use disease formation or large scale chromosomal alterations as an assay for gene alteration.
The problem of detecting small scale DNA alterations that are caused by potential mutagenic agents has generally been approached by performing studies on cells in culture (in vitro tests). The well-known Ame's test uses a special strain of bacteria to detect these mutation. Ames, et al., An Improved Bacterial Test System for the Detection and Classification of Mutagens and Carcinogens, Proc. Nat. Acad. Sci. 70:782-86 (1973). This test and many analogues that use other types of bacterial or animal cells permit the rapid screening of very large numbers of cells for the appearance of an altered phenotype. The appearance of this altered phenotypic trait reflects the occurrence of a mutation within the test gene. These tests are, however, insensitive to or nonspecific for many mutagens that result from metabolic activation of the agent being screened. Although attempts have been made to increase their sensitivity and specificity by activation of such metabolites with liver and other extracts it is noted that, for instance, the metabolites produced by these extracts are often not present at the same concentration as in the live tissues of an animal. Metabolites that are only produced in other organs are not detected at all.
Eukaryotic cell lines have also been used to detect mutations. E.g., Glazer et al., Detection and Analysis of UV-induced Mutations in Mammalian Cell DNA using Lambda Phage Shuttle Vector., Proc. Natl. Acad. Sci. USA 83:1041-1044 (1986). In this test a target test gene, the amber suppressor tyrosine tRNA gene of E. coli in a bacteriophage shuttle vector, was integrated into a genomic host mammalian cell line by DNA transfection. After exposing the host cell line to putative mutagenic agents, test genes were re-isolated, propagated in bacteria, and analyzed for mutations. Because the host is only a mammalian cell line and not a live animal, the test is incapable of accurately monitoring mutagenic metabolites of the agent being tested that are only produced at the appropriate concentrations by differentiated cells or the tissue of live animals.
Such test genes and large scale screening assays are not available for live animal studies. Short of relying on longterm animal studies that detect phenotypic changes that require a long time to be identifiable, such as tumors, organ failure, etc., current tests do not provide a means for monitoring organ-specific mutations of DNA. Hence, there exists a need for a system that places a test DNA sequence within an animal and is subsequently assayed on a large scale for mutations. There also exists a need for a test that detects mutations caused by chemical metabolites of the agent being tested. To be most effective the system needs to be capable of monitoring small genetic changes in as many tissues of an animal and as easily, rapidly, and inexpensively as possible.
The present invention produces a test that satisfies these needs. The test is a sensitive screen for the mutagenicity of all agents. The test not only monitors the mutagenic effects of the agent being screened it also monitors the mutagenic effects of all metabolites that occur in animal tissues of the agent being tested. It permits the identification of the nature of the mutation: e.g., DNA transition, transversion, deletion, or a point or frameshift mutation. The test is rapid and it is inexpensive relative to other tests. And, it will spot a potential mutagen rapidly before other more expensive tests can be completed.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, forming a portion of this disclosure:
FIG. 1 illustrates the sequence of process steps for performing the invention.
FIG. 2 illustrates an alternative method for recovering the transgenic test DNA sequence.
SUMMARY OF THE INVENTION
The present invention involves the introduction of at least one copy of at least one target DNA sequence into the cells of a non-human animal that is then bred to produce test animals. This test transgenic animal is then exposed to an agent that is suspected to be mutagenic. The target test DNA sequence is subsequently recovered from individual tissues of the transgenic animal and is transferred into a microorganism, where it can be assayed for mutations, allowing rapid examination of multiple tissue specific genetic mutations.
Theoretically, any animal suitable for mutagenic testing may be used as the starting organism. In order to allow for ubiquitous insertion of the novel test sequence, single cell animal embryos can be harvested, although there may be other cells facilitating the uptake and ultimate ubiquitous presence of the marker DNA in every cell of a differentiated animal.
A test DNA sequence must be prepared for insertion into the animal. Any number or variety of sequences coding for a phenotype or genotype that is easily detectable upon mutation may be used. A vector capable of facilitating the recovery of the test DNA sequence from the host animal cells, and capable of allowing autonomous replication and expression of the sequence in the anticipated bacterial host may be used as a carrier for the target test DNA sequence. Thus, the construct for such a vector and insert should contain, at least, regions that allow insertion into and excision from the animal host genome, and regions that allow autonomous replication in the bacterial host cell, as well as regions that allow expression and assay of the test DNA sequence. If integration into the host genome is not required, desired regions that allow for replication of the test DNA sequence in the animal host cells should be present. Elbrecht, A., DeMayo, F. J., Tsai, M., and O'Malley, B. W. (1987). Episomal maintenance of a bovine papilloma virus vector in transgenic mice. Mol. Cell. Biol. 7:1276-1279.
A next step involves transforming the host animal with the test DNA sequence, so as to provide the stable presence of the test sequence throughout cells of the differentiated animal. Typically, this involves the integration of the test DNA sequence into the animal host genome, although methods that allow the test sequence to be stably and heritably present through the use of autonomously replicating vectors may also be useful. Elbrecht, A., DeMayo, F. J., Tsai, M., and O'Malley, B. W. (1987). Episomal maintenance of a bovine papilloma virus vector in transgenic mice. Mol. Cell. Biol. 7:1276-1279. The vector containing the test DNA sequence must be physically introduced into the animal. At the cellular level, this may be accomplished using the techniques of microinjection, electroporation, dielectrophoresis or various chemically mediated transformation techniques, all of which are well known in the art. At the differentiated tissue level, other techniques may be necessary.
Once the test DNA sequence has been introduced and has integrated into the genome or cell, the transgenic cells must be allowed to differentiate into a whole organism. This may be done, for example, by embryo implantation into pseudopregnant females, or by other techniques allowing maturation of transgenic embryos. Once such maturation and differentiation has occurred, the animal is assayed for the presence of the test DNA sequence. Typically this involves removing small portions of tissue from the animal and using DNA hybridization assay techniques to detect the presence of the test DNA sequence.
If the animal carries the test DNA sequence, the animal may be bred and its offspring that carry the transgenic DNA sequence may be used for studies of mutagenesis. The test animal is exposed to the agent or substance in question under appropriate conditions. Such conditions will depend, for example, on the nature of the agent or substance, the purpose of the mutagenesis study and the type of data desired.
After exposure of test transgenic animals to the agent to be tested under the desired conditions, tissues are removed from the test animal. Because the test DNA sequence is present in essentially all tissues, the tissue type tested is not limited by the process of insertion of the test sequence. Any desired tissue may be removed. Genomic DNA is purified from the tissue.
The target test DNA sequence which is integrated is rescued from the total genomic DNA of the host. This may be accomplished by excising it from the host genome or by any procedures allowing separation by size, weight or charge density. The method of rescue is dependent upon whether test DNA sequence is inserted into the genome, and whether flanking regions allow for excision, or whether the test DNA sequence is part of an autonomously replicating element allowing for separation techniques.
The rescued test DNA sequences are then transferred into and expressed by microorganisms appropriate for large scale screening techniques. Typically this involves excising the test DNA sequence vector from the genomic DNA by packaging the test DNA sequence with bacteriophage packaging techniques, but it may require ligating the test DNA sequence into an appropriate vector or merely require direct transformation into a microorganism.
The microorganisms containing the test DNA sequence vector are then grown on indicator plates or in selective media. Those organisms having a phenotype indicating mutation of the test DNA sequence may be considered to contain a mutated test DNA sequence. The ratio of those organisms expressing mutated phenotype of test sequences to the total number of organisms containing the test DNA sequence is a measure of the mutagenicity of the agent and metabolites of it present in the tested tissue.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description provides details of the manner in which the embodiments of the present invention may be made and used in order to achieve the rapid recovery and examination of test DNA sequences from transgenic animals. This description, while exemplary of the present invention, is not to be construed as specifically limiting the invention. Such variations and equivalents, now known or later developed, that would be within the purview of one skilled in this art are to be considered to fall within the scope of this invention, which is limited only as set forth by the appended claims.
A. Creation of a Transgenic Animal
Mice were used as the test animal. Single cell mouse embryos were harvested from female mice that were impregnated the evening before. The embryos were treated with hyaluronidase and briefly cultured in M16 medium. The embryos were transferred to M2 medium on a microscope glass depression slide. The embryos were observed with a 40 X objective and a 10 X eyepiece using a Nikon Diaphot microscope equipped with Hoffman optics. The embryos were held in place with a holding pipet that had been rounded with a microforge. The positions of both the holding pipets and the injection pipets were controlled with micromanipulators. DNA as described below was loaded in the injection pipet at a concentration of 1 to 10 micrograms per milliliter. Approximately one picoliter, as judged by a refractile change of the pronucleus, of DNA solution was injected into the male pronucleus.
After DNA injection, the embryos were transferred to M16 medium and incubated at 37° C. in a 5% CO2 atmosphere for one to two hours. Lysed embryos were discarded and embryos that appeared normal were transferred to one of the fallopian tubes of pseudopregnant foster mothers. The transfers were performed under a dissecting microscope using general anesthesia (avertin).
After birth, newborn mice were kept with their foster mothers for 2 weeks, at which point they were then weaned and screened for DNA integration. A 2 cm portion of the tail was removed and homogenized in 2 ml of a solution of 0.1M NaCl, 50 mM Tris-HCl, pH 7.5, 1 mM EDTA for short duration, but long enough to disrupt cell and nuclear membranes. The homogenized tissue was treated with 50 U/ml RNaseA and 0.1% SDS for 15 minutes at 37° C. The mixture was exposed to Proteinase K digestion for 3 hours at 55° C. followed by three extractions with phenol/chloroform. DNA was then precipitated by the addition of ethanol. After resuspending the precipitated DNA in 10 mM Tris pH 8.0, 0.5 mM EDTA, some of it was digested with BamHI endonuclease and electrophoresed through an 0.8% agarose gel. The DNA was denatured by soaking the gel in 1.5M NaCl, 0.5M NaOH for one hour and then neutralizing the DNA by soaking it in 1.5M NaCl, 0.5M Tris, pH 7.4 for 30 minutes. The gel was then soaked in 10 X SSC for one hour. The DNA was then transferred from the gel onto a nitrocellulose filter by the method of Southern, as described in Maniatis, T., Fritsch, E. F., Sambrook, J., Molecular Cloning, A Laboratory Manual, pp. 109-110, 383-389 (Cold Spring Harbor, N. Y. 1982).
The filter with transferred DNA was hybridized overnight with 32 P labeled lambda DNA prepared, according to standard procedures, by the method of nick translation. Maniatis, supra. Following this overnight hybridization, the filter was washed in 0.1×SSC, 0.1% SDS at 50° C. and Kodak XAR film was exposed to it in order to identify lambda DNA present within the mouse genome. Lambda DNA, used as standards, that had been electrophoresed alongside the mouse genomic DNA were compared in intensity to the transgenic mouse DNA hybridized to the 32 P labeled lambda DNA to estimate copy number. Numerous transgenic animals have been produced and identified by this technique and most of them transmit the integrated DNA to their offspring, demonstrating germ line integration.
The test sequence DNA can, theoretically, contain any number or variety of genes or other identifiable test DNA sequences. In the prototype described herein, an E. coli bacteriophage lambda genome has been engineered to carry a beta-galactosidase test DNA sequence. The genotype of the modified lambda genome L2B is lac5 delta (shindIII lambda 2°-3°) srI lambda 3°-5° cI857 sXhl lambda 1° sScII lambda 4°. Before injecting it into mouse embryos, this lambda DNA was diluted to a concentration of 10 micrograms per milliliter and the cos ends were annealed and ligated under conditions predominantly forming circular lambda phage monomers. Maniatis, supra.
Newborn mice were tested for the presence of the test DNA sequence by the tail-blotting procedure. Hogan, et al., Manipulating the Mouse Embroyo: A Laboratory Manual, pp. 174-183 (Cold Spring Harbor Laboratory, 1986). Several of the newborns were found to carry the test DNA sequence in DNA isolated from their tails. Eight weeks after birth these transgenic mice were mated and their progeny were examined for the test DNA sequence. Approximately 50% of the resulting offspring carried the test DNA sequence, demonstrating that the original transgenic mice carried the test DNA sequence in their germ line and that this sequence was inherited normally. While transgenic lines having approximately one copy of the test DNA sequence per cell can be obtained, lines having at least about 5-10 copies per cell are preferred. This is believed to make the rescue procedure more efficient. Mouse embryos of a progeny of a transgenic mouse produced and identified by this technique and containing the beta-galactosidase test DNA sequence have been deposited with the American Type Culture Collection (ATCC; Rockville, Md.) having an ATCC accession number 72011.
B. Mutagenesis Testing Using Transgenic Animals Carrying Test DNA Sequence
The target vector lambda L2B can be used initially to establish background mutagenesis rates within transgenic mouse strains. A variation of L2B may be constructed that also contains a plasmid sequence that can be readily excised from the lambda phage and contains the Lac I gene. This variation may have two advantages. First, mutations will appear as blue plaques on a white background in the presence of X-gal (5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside) without IPTG (isopropylβ-D-thiogalactopyranoside). This should aid in the identification of mutations. Second, the blue plaques will represent Lac I mutations which may be isolated and rapidly assessed.
When genomic DNA is purified from any tissue of the transgenic mouse, the test DNA sequence can be found within the genomic DNA. Since the test DNA sequence is contained within a lambda phage genome, it can be excised away from the remainder of the genomic DNA by using a lambda phage packaging extract. Approximately 10 micrograms of genomic DNA (isolated as described above) is added to 100 microliters of lambda phage packaging extract (Gigapack Gold, Stratagene Cloning Systems, San Diego, Calif.) and incubated for 2 hours at 23° C. The reaction is then diluted with 5000 microliters of SM (100 mM NaCl, 8 mM MgSO4 7H2 O, 50 mM. Tris, pH 7.5, 0.01% gelatin) and 200 microliters of chloroform. The reaction mixture is then added to 2×109 β-galactosidase deficient E. coli that have been grown in the presence of 0.2% maltose and 10 mM MgCl2. After incubating at 37° C. for 15 minutes, 7 milliliters of liquid top agarose (85 mM NaCl, 8 mM MgSo4 7H2 O, 5 g/l yeast extract, 10 g/l NZamine, 0.7% agarose at 48° C.) is added and the mixture is poured onto a petri dish containing nutrient agar supplemented with X-Gal (4 mg/ml) and IPTG (1 mM). The plates are incubated overnight at 37° C. Rescued test lac I sequences appear as plaques of lysed bacteria on a confluent "lawn" of E. coli.
In the presence of X-gal (5-bromo-4-chloro-3-indoyl-β-D-galactoside) and IPTG, the phage plaques turn blue if the beta-galactosidase sequence within the lambda genome has not mutated. However, a white plaque on the petri dish is evidence that a mutation in the beta-galactosidase sequence has, for example, altered the reading fram, altered essential codons, or have created stop codons in the sequence. These white plaques will be scored as positive for mutations and they can be plaque purified and saved for further analysis. The ratio of white to blue plaques minus background will indicate the mutagenesis potency of the agent being tested when compared with DNA extracted from mice that have not been treated with potentially mutagenic agents.
In the embodiment described here, rescue of the marker DNA sequence is possible because it is contained within a lambda bacteriophage genome. The entire lambda bacteriophage genome is excised from the mouse chromosome by the in vitro packaging extract. The packaging extract recognizes the cos sites of the integrated lambda DNA and packages the sequences between the cos sites into lambda phage particles, as shown in FIG. 1.
It is anticipated that test DNA sequence rescue efficiency can be influenced by the state of CpG methylation in the mouse chromosome. Highly methylated DNA may not be efficiently excised by lambda packaging extract, presumably because of inhibition of cleavage at the cos sites. It is anticipated that this can be alleviated by placing transcriptional enhancers, promoters and/or other regions of the DNA which inhibit methylation near the cos site to reduce CpG methylation. The drug 5'-azacytidine can also be used to reduce the level of DNA methylation in the target cells prior to DNA purification and rescue. Jaenisch, R., et al., Proc. Natl. Acad. Sci. USA 82:1451-1455 (1985). In such a procedure, fibroblast cell lines are obtained from organisms containing the test DNA sequence of interest. Adams, R. L. P., Cell Culture for Biochemists, pages 68-83 (1980 Elselvier/North Holland Biomedical Press). The cells are exposed in vitro at 37° C., with 50 μm 5'azacytidine supplementing the culture medium. Upon DNA replication, the daughter DNA loses its CgG methylation, which eliminates the methylation of cos sites in the target vector, where the target vector is a lambda phage. The DNA from these fibroblasts is then exposed to in vitro packaging extract, as previously described.
Alternatively, organisms containing the test DNA sequence can be directly injected with a 1 mg/ml solution of 5'-azacytidine in 0.15M NaCl. This is done over a period of at least 4 days, with a total of 400 μg administered. Jaenisch, supra. After this treatment, DNA can be extracted from various tissues and packaged as before.
Of course, any number or variety of test DNA sequence or gene can be inserted between lambda cos sites. The in vitro packaging extract would still excise the DNA between the cos sites and insert it into a lambda phage particle. Thus, a variety of recombinant lambda genomes or cosmids may be used for this excision event.
The embodiment described above utilizes the E. coli beta-galactosidase gene as a test DNA sequence, which allows phenotypes that are positive and negative for mutation to be observed. Other potential test DNA sequences include (but are not limited to): the lac I repressor, the cl repressor, any antibiotic resistance gene sequence (ampicillin, kanamycin, tetracycline, neomycin, chloroamphenicol, etc.), the lambda red and gam gene sequences, a thymidine kinase gene sequence, a xanthine-guanine phosphoribosyl transferase gene sequence, sequences that code for restriction enzymes or methylation enzymes, a gene sequence that codes for luciferase, and/or a tRNA stop codon or frameshift suppressor gene sequence.
Even more general models can be made that eliminate the cos sites, although the excision mechanism now becomes different. By bracketing the test DNA sequence(s) with convenient restriction sites, as shown in FIG. 2, the test sequence(s) can be separated away from the mouse DNA with restriction enzymes and subsequently ligated with lambda or cosmid vectors which contain cos sites. Background can be reduced in such a system by including with the test DNA sequences a sequence that is necessary for lambda phage replication, which is then cloned with the test DNA sequence into a lambda genome deficient or defective in that sequence.

Claims (3)

We claim:
1. A transgenic mouse whose somatic and germ cells contain the beta-galactosidase gene flanked by the bacteriophage lambda cos sites, and the expression of said beta-galactosidase gene being capable of detection in E. coli.
2. The transgenic mouse of claim 1, wherein said beta-galactosidase gene is carried in a modified bacteriophage lambda genome L2B.
3. The transgenic mouse of claim 2 which is derived from a mouse embryo deposited with the American Type Culture Collection and having an ATCC accession number 72011.
US07/711,332 1987-05-01 1991-06-06 Mutagenesis testing using transgenic non-human animals carrying test DNA sequences Expired - Lifetime US5347075A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US07/711,332 US5347075A (en) 1987-05-01 1991-06-06 Mutagenesis testing using transgenic non-human animals carrying test DNA sequences

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US4503787A 1987-05-01 1987-05-01
US07/711,332 US5347075A (en) 1987-05-01 1991-06-06 Mutagenesis testing using transgenic non-human animals carrying test DNA sequences

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US4503787A Continuation 1987-05-01 1987-05-01

Publications (1)

Publication Number Publication Date
US5347075A true US5347075A (en) 1994-09-13

Family

ID=21935674

Family Applications (1)

Application Number Title Priority Date Filing Date
US07/711,332 Expired - Lifetime US5347075A (en) 1987-05-01 1991-06-06 Mutagenesis testing using transgenic non-human animals carrying test DNA sequences

Country Status (5)

Country Link
US (1) US5347075A (en)
EP (1) EP0289121B1 (en)
JP (1) JP2618973B2 (en)
AT (1) ATE132266T1 (en)
DE (1) DE3854823T2 (en)

Cited By (63)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5470706A (en) * 1988-07-19 1995-11-28 Nederlandse Organisatie Voor Toegepastwetenschappelijk Onderzoek Tno Process for the rescue of DNA and for detecting mutations in marker genes
US5510099A (en) * 1987-05-01 1996-04-23 Stratagene Mutagenesis testing using transgenic non-human animals carrying test DNA sequences
US5589155A (en) * 1987-05-01 1996-12-31 Union Bank Of California, N.A. Mutagenesis testing using transgenic non-human animals carrying test DNA sequences
US5602300A (en) * 1991-04-02 1997-02-11 Ingeny B.V. Process for detecting mutations, transgenic mammal transgenic mammalian cell, and process for testing agents or conditioning for mutagenic properties
US5728807A (en) * 1995-05-16 1998-03-17 Ramot-University Authority For Applied Research And Industrial Development, Ltd. Mutated proteins associated with ataxia-telangiectasia
US5777093A (en) * 1995-05-16 1998-07-07 Ramot-University Authority For Applied Research & Industrial Development Ltd. cDNAs associated with ataxia-telangiectasia
US5821049A (en) * 1996-04-05 1998-10-13 Viratest Carcinogen Monitoring, Ltd In vitro assay for identification of carcinogens
US5824838A (en) * 1996-05-09 1998-10-20 Cedars-Sinai Medical Center Transgenic mouse model for pituitary disorders associated with LIF overexpression and/or GH underexpression, and its use for testing therapeutic drugs for the conditions
US5837535A (en) * 1994-06-13 1998-11-17 Henry Ford Health System Neuronal-neonatal gene: neuronatin
US5858661A (en) * 1995-05-16 1999-01-12 Ramot-University Authority For Applied Research And Industrial Development Ataxia-telangiectasia gene and its genomic organization
US5898094A (en) * 1996-10-21 1999-04-27 University Of South Florida Transgenic mice expressing APPK670N,M671L and a mutant presenilin transgenes
US5968773A (en) * 1997-11-14 1999-10-19 Heddle; John A. System and method for regulation of gene expression
US5994075A (en) * 1996-05-17 1999-11-30 Hexagen Technology Limited Methods for identifying a mutation in a gene of interest without a phenotypic guide
US6015670A (en) * 1996-05-17 2000-01-18 Hexagen Technology Limited Methods for identifying a mutation in a gene of interest without a phenotypic guide using ES cells
US6025183A (en) * 1994-02-28 2000-02-15 Yissum Research Development Company Of The Hebrew University Of Jerusalem Transgenic animal assay system for anti-cholinesterase substances
US6057489A (en) * 1996-09-12 2000-05-02 M.D. Anderson Cancer Center MmRad51-deficient cells and transgenic mice
WO2000032773A1 (en) 1998-11-27 2000-06-08 Darwin Discovery Ltd. Compositions and methods for increasing bone mineralization
US6140309A (en) * 1996-03-12 2000-10-31 University Of South Florida Vasoactive effects and free radical generation by β-amyloid peptides
US6153429A (en) * 1996-04-05 2000-11-28 Vera Genics Ltd. Cell lines useful for in vitro assay for indentification of carcinogens
US6248555B1 (en) 1995-08-31 2001-06-19 The General Hospital Corporation Genetic alterations related to familial alzheimer's disease
US6264915B1 (en) 1992-09-13 2001-07-24 The President And Fellows Of Harvard College Process for detecting potential carcinogens
US6307121B1 (en) 1998-05-31 2001-10-23 The University Of Georgia Research Foundation, Inc. Bacteriophage-based transgenic fish for mutation detection
US6455674B1 (en) 1997-08-21 2002-09-24 Quark Biotech, Inc. Hypoxia-regulated genes
US6472583B1 (en) 1998-10-26 2002-10-29 The University Of Georgia Research Foundation, Inc. Plasmid-based mutation detection system in transgenic fish
US20030086914A1 (en) * 1999-06-25 2003-05-08 Yissum Research Development Company Of The Hebrew University Of Jerusalem Method and device for inducing biological processes by micro-organs
US20030100490A1 (en) * 1999-04-01 2003-05-29 Tony Cruz Compositions and methods for treating cellular response to injury and other proliferating cell disorders regulated by hyaladherin and hyaluronans
US20030104973A1 (en) * 1997-08-21 2003-06-05 Quark Biotech, Inc. Hypoxia-regulated genes
US20030131364A1 (en) * 1999-04-27 2003-07-10 Karen Duff Method for producing transgenic animal models with modulated phenotype and animals produced therefrom
US20030152909A1 (en) * 1994-11-16 2003-08-14 Mitrani Eduardo N. In vitro micro-organs, and uses related thereto
US20030211490A1 (en) * 2000-01-24 2003-11-13 Hanan Stein Plants tolerant of environmental stress conditions, methods of generating same and novel polynucleotide sequence utilized thereby
US20040005571A1 (en) * 2002-07-03 2004-01-08 Hawley R. Scott Axs gene and protein and methods related thereto
US20040078847A1 (en) * 2001-03-22 2004-04-22 Nitzan Paldi Method of enhancing entomophilous
US20040146949A1 (en) * 2002-10-25 2004-07-29 Jun Tan Methods and compounds for disruption of CD40R/CD40L signaling in the treatment of alzheimer's disease
US6787318B1 (en) 1999-06-01 2004-09-07 Roskamp Research Institute, Llc Assay for evaluating the therapeutic effectiveness of agents in reducing Alzheimer's disease pathology
US20040197798A1 (en) * 1995-09-01 2004-10-07 Ramot University Authority For Applied Research And Industrial Development Ltd. Manipulation and detection of protein phosphatase 2C - PP2Calpha - expression in tumor cells for cancer therapy, prevention and detection
US6864235B1 (en) 1999-04-01 2005-03-08 Eva A. Turley Compositions and methods for treating cellular response to injury and other proliferating cell disorders regulated by hyaladherin and hyaluronans
US6875582B1 (en) 1999-08-19 2005-04-05 Omniscience Pharmaceuticals, Inc. Methods and targets of antibiotic resistance
US20050095240A1 (en) * 2002-11-22 2005-05-05 Medical College Of Georgia Research NaCT as a target for lifespan expansion and weight reduction
US20060019241A1 (en) * 2004-04-20 2006-01-26 Vadivel Ganapathy Na+ and CI-coupled transport system for endogenous opioid peptides
US6998232B1 (en) 1999-09-27 2006-02-14 Quark Biotech, Inc. Methods of diagnosing bladder cancer
US20060051426A1 (en) * 2001-12-05 2006-03-09 Gershon Golomb Nanoparticles containing polymeric nucleic acid homologs pharmaceutical composition and articles of manufacture containing same and methods of use thereof
US20060127366A1 (en) * 1999-06-25 2006-06-15 Mitrani Eduardo N Method and device for inducing biological processes by micro-organs
US20060206950A1 (en) * 2002-11-04 2006-09-14 Kaelin William G Jr In vivo imaging of e2f-fegulated bioluminescent proteins
US20070032421A1 (en) * 2003-12-12 2007-02-08 Efrat Levy Methods and compositions relating to cystatin C
US7223849B1 (en) 1996-07-01 2007-05-29 Genesense Technologies Inc. Oligonucleotides from the untranslated regions of housekeeping genes and methods of using same to modulate cell growth
US20070160615A1 (en) * 1999-06-01 2007-07-12 Jun Tan Methods and compounds for disruption of CD40R/CD40L signaling in the treatment of Alzheimer's disease
WO2007088418A1 (en) 2006-01-31 2007-08-09 Multi Gene Vascular Systems, Inc. Drug-eluting intravascular prostheses and methods of use
EP1967525A2 (en) 2001-05-08 2008-09-10 Darwin Molecular Corporation A method for regulating immune function in primates using the foxp3 protein
US20080227692A1 (en) * 2007-03-16 2008-09-18 Moshe Flugelman Compositions and methods for treating ophthalmic disorders
WO2008120202A2 (en) 2007-03-29 2008-10-09 Technion Research & Development Foundation Ltd. Antibodies, methods and kits for diagnosing and treating melanoma
EP2009109A1 (en) 1998-01-12 2008-12-31 Pedro Jose G protein-related kinase mutants in essential hypertension
US20090017112A1 (en) * 2006-03-01 2009-01-15 Roskamp Research Llc Compounds for Inhibiting Beta-Amyloid Production
US20090036662A1 (en) * 1997-08-21 2009-02-05 Paz Einat Hypoxia-regulated genes
EP2072045A2 (en) 2002-02-13 2009-06-24 Technion Research and Development Foundation, Ltd. Antibody having a t-cell receptor-like specificity, yet higher affinity, and the use of same in the detection and treatment of cancer, viral infection and autoimmune disease
US7687057B2 (en) 1998-01-09 2010-03-30 Yissum Research Development Company Of The Hebrew University Of Jerusalem In vitro micro-organs, and uses related thereto
US20100119599A1 (en) * 2006-12-08 2010-05-13 Archer Pharmaceuticals, Inc. Polyhydroquinoline compounds and dihydropyridine compounds for inhibiting beta-amyloid production
EP2338906A1 (en) 2003-06-16 2011-06-29 UCB Manufacturing, Inc. Compostion and methods for increasing bone mineralization
US8088160B2 (en) 2000-07-20 2012-01-03 Multi-Gene Vascular Systems Ltd. (“MGVS”) Drug-eluting intravascular prostheses and methods of use
EP2526953A1 (en) 2003-07-15 2012-11-28 Bar-Ilan University Methods and pharmaceutical compositions for healing wounds
US8454948B2 (en) 2006-09-14 2013-06-04 Medgenics Medical Israel Ltd. Long lasting drug formulations
US8586024B2 (en) 2006-09-14 2013-11-19 Medgenics Medical Israel Ltd. Long lasting drug formulations
WO2015059701A1 (en) 2013-10-24 2015-04-30 Medgenics Medical Israel Ltd. Micro-organs providing sustained delivery of a therapeutic polypeptide and methods of use thereof
US9127084B2 (en) 2006-09-14 2015-09-08 Medgenics Medical Israel Ltd. Long lasting drug formulations

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0390857A4 (en) * 1987-12-15 1991-04-17 The Trustees Of Princeton University Transgenic testing systems for mutagens and carcinogens
WO1989009272A1 (en) * 1988-03-22 1989-10-05 Chemical Industry Institute Of Toxicology A transgenic mouse for measurement and characterization of mutation induction in vivo
EP0370813A3 (en) * 1988-11-25 1991-06-19 Exemplar Corporation Rapid screening mutagenesis and teratogenesis assay
FR2646438B1 (en) 1989-03-20 2007-11-02 Pasteur Institut A METHOD FOR SPECIFIC REPLACEMENT OF A COPY OF A GENE PRESENT IN THE RECEIVER GENOME BY INTEGRATION OF A GENE DIFFERENT FROM THAT OR INTEGRATION
GB9003791D0 (en) * 1990-02-20 1990-04-18 Ludwig Inst Cancer Res Transgenic animals,cell lines therefrom,and their use
JPH06506103A (en) * 1990-04-05 1994-07-14 ストラタジーン Mutagenicity tests using transgenic non-human animals carrying test DNA sequences
US5866759A (en) * 1991-02-20 1999-02-02 Ludwig Institute For Cancer Research Transgenic mice expressing TSSV40 large T antigen
AU2013192A (en) * 1991-06-07 1993-01-08 United States Of America, Represented By The Secretary, Department Of Health And Human Services, The Phi x174 transgenic mammals
EP0671955A4 (en) * 1992-02-14 1997-04-09 Stratagene Inc Mutagenesis testing using transgenic non-human animals carrying test dna sequences.
AU3777693A (en) * 1992-02-27 1993-09-13 Ohio University Mutagenicity testing using reporter genes with modified methylation frequencies
AU4220093A (en) * 1992-04-27 1993-11-29 Indiana University Foundation Live animal mutagenesis systems for testing mutagenic agents in vivo

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4736866A (en) * 1984-06-22 1988-04-12 President And Fellows Of Harvard College Transgenic non-human mammals

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4736866A (en) * 1984-06-22 1988-04-12 President And Fellows Of Harvard College Transgenic non-human mammals
US4736866B1 (en) * 1984-06-22 1988-04-12 Transgenic non-human mammals

Non-Patent Citations (12)

* Cited by examiner, † Cited by third party
Title
Glazer et al., Proc. Natl. Acad. Sci. 83: 1041 1044 (1986). *
Glazer et al., Proc. Natl. Acad. Sci. 83: 1041-1044 (1986).
Lohman et al., Mutation Res. 181: 227 234 (1987). *
Lohman et al., Mutation Res. 181: 227-234 (1987).
Palmiter et al., Cell 41: 343 345 (1985). *
Palmiter et al., Cell 41: 343-345 (1985).
Singh et al., Canadian J. Genet. & Cytology 28: 286 293 (1986). *
Singh et al., Canadian J. Genet. & Cytology 28: 286-293 (1986).
Summers et al., Mutation Res. 220: 263 268 (1989). *
Summers et al., Mutation Res. 220: 263-268 (1989).
Tice et al., "Modern Biological Theories of Aging" Warner et al., eds, p. 214, Raven Press (1987).
Tice et al., Modern Biological Theories of Aging Warner et al., eds, p. 214, Raven Press (1987). *

Cited By (87)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5510099A (en) * 1987-05-01 1996-04-23 Stratagene Mutagenesis testing using transgenic non-human animals carrying test DNA sequences
US5589155A (en) * 1987-05-01 1996-12-31 Union Bank Of California, N.A. Mutagenesis testing using transgenic non-human animals carrying test DNA sequences
US5470706A (en) * 1988-07-19 1995-11-28 Nederlandse Organisatie Voor Toegepastwetenschappelijk Onderzoek Tno Process for the rescue of DNA and for detecting mutations in marker genes
US5602300A (en) * 1991-04-02 1997-02-11 Ingeny B.V. Process for detecting mutations, transgenic mammal transgenic mammalian cell, and process for testing agents or conditioning for mutagenic properties
US6264915B1 (en) 1992-09-13 2001-07-24 The President And Fellows Of Harvard College Process for detecting potential carcinogens
US6025183A (en) * 1994-02-28 2000-02-15 Yissum Research Development Company Of The Hebrew University Of Jerusalem Transgenic animal assay system for anti-cholinesterase substances
US5837535A (en) * 1994-06-13 1998-11-17 Henry Ford Health System Neuronal-neonatal gene: neuronatin
US20030152909A1 (en) * 1994-11-16 2003-08-14 Mitrani Eduardo N. In vitro micro-organs, and uses related thereto
US5728807A (en) * 1995-05-16 1998-03-17 Ramot-University Authority For Applied Research And Industrial Development, Ltd. Mutated proteins associated with ataxia-telangiectasia
US5858661A (en) * 1995-05-16 1999-01-12 Ramot-University Authority For Applied Research And Industrial Development Ataxia-telangiectasia gene and its genomic organization
US5777093A (en) * 1995-05-16 1998-07-07 Ramot-University Authority For Applied Research & Industrial Development Ltd. cDNAs associated with ataxia-telangiectasia
US6200749B1 (en) 1995-05-16 2001-03-13 Ramot-University Authority For Applied Research And Industrial Development Ltd. Mutated forms of the ataxia-telangiectasia gene and method to screen for a partial A-T phenotype
US20010012626A1 (en) * 1995-08-31 2001-08-09 The General Hospital Corporation Genetic alterations related to familial alzheimer's disease
US6248555B1 (en) 1995-08-31 2001-06-19 The General Hospital Corporation Genetic alterations related to familial alzheimer's disease
US20040197798A1 (en) * 1995-09-01 2004-10-07 Ramot University Authority For Applied Research And Industrial Development Ltd. Manipulation and detection of protein phosphatase 2C - PP2Calpha - expression in tumor cells for cancer therapy, prevention and detection
US6140309A (en) * 1996-03-12 2000-10-31 University Of South Florida Vasoactive effects and free radical generation by β-amyloid peptides
US6153429A (en) * 1996-04-05 2000-11-28 Vera Genics Ltd. Cell lines useful for in vitro assay for indentification of carcinogens
US5821049A (en) * 1996-04-05 1998-10-13 Viratest Carcinogen Monitoring, Ltd In vitro assay for identification of carcinogens
US5824838A (en) * 1996-05-09 1998-10-20 Cedars-Sinai Medical Center Transgenic mouse model for pituitary disorders associated with LIF overexpression and/or GH underexpression, and its use for testing therapeutic drugs for the conditions
US6015670A (en) * 1996-05-17 2000-01-18 Hexagen Technology Limited Methods for identifying a mutation in a gene of interest without a phenotypic guide using ES cells
US5994075A (en) * 1996-05-17 1999-11-30 Hexagen Technology Limited Methods for identifying a mutation in a gene of interest without a phenotypic guide
US7223849B1 (en) 1996-07-01 2007-05-29 Genesense Technologies Inc. Oligonucleotides from the untranslated regions of housekeeping genes and methods of using same to modulate cell growth
US6057489A (en) * 1996-09-12 2000-05-02 M.D. Anderson Cancer Center MmRad51-deficient cells and transgenic mice
US5898094A (en) * 1996-10-21 1999-04-27 University Of South Florida Transgenic mice expressing APPK670N,M671L and a mutant presenilin transgenes
US20030124116A1 (en) * 1997-08-21 2003-07-03 Quark Biotech, Inc. Hypoxia-regulated genes
US6555667B1 (en) 1997-08-21 2003-04-29 Quark Biotech, Inc. Hypoxia-regulated genes
US7973156B2 (en) 1997-08-21 2011-07-05 Quark Pharmaceuticals Inc. Hypoxia-regulated genes
US20030104973A1 (en) * 1997-08-21 2003-06-05 Quark Biotech, Inc. Hypoxia-regulated genes
US6740738B2 (en) 1997-08-21 2004-05-25 Quark Biotech, Inc. Antibody against hypoxia proteins
US6455674B1 (en) 1997-08-21 2002-09-24 Quark Biotech, Inc. Hypoxia-regulated genes
US20090036662A1 (en) * 1997-08-21 2009-02-05 Paz Einat Hypoxia-regulated genes
US5968773A (en) * 1997-11-14 1999-10-19 Heddle; John A. System and method for regulation of gene expression
US7687057B2 (en) 1998-01-09 2010-03-30 Yissum Research Development Company Of The Hebrew University Of Jerusalem In vitro micro-organs, and uses related thereto
EP2009109A1 (en) 1998-01-12 2008-12-31 Pedro Jose G protein-related kinase mutants in essential hypertension
US6307121B1 (en) 1998-05-31 2001-10-23 The University Of Georgia Research Foundation, Inc. Bacteriophage-based transgenic fish for mutation detection
US6472583B1 (en) 1998-10-26 2002-10-29 The University Of Georgia Research Foundation, Inc. Plasmid-based mutation detection system in transgenic fish
WO2000032773A1 (en) 1998-11-27 2000-06-08 Darwin Discovery Ltd. Compositions and methods for increasing bone mineralization
EP2261335A1 (en) 1998-11-27 2010-12-15 UCB Pharma S.A. Compositions and methods for increasing bone mineralisation
US20050065085A1 (en) * 1999-04-01 2005-03-24 Transition Therapeutics Inc. Compositions and methods for treating cellular response to injury and other proliferating cell disorders regulated by hyaladherin and hyaluronans
US6911429B2 (en) 1999-04-01 2005-06-28 Transition Therapeutics Inc. Compositions and methods for treating cellular response to injury and other proliferating cell disorders regulated by hyaladherin and hyaluronans
US6864235B1 (en) 1999-04-01 2005-03-08 Eva A. Turley Compositions and methods for treating cellular response to injury and other proliferating cell disorders regulated by hyaladherin and hyaluronans
US20050058646A1 (en) * 1999-04-01 2005-03-17 Turley Eva A. Compositions and methods for treating cellular response to injury and other proliferating cell disorders regulated by hyaladherin and hyalurons
US20030100490A1 (en) * 1999-04-01 2003-05-29 Tony Cruz Compositions and methods for treating cellular response to injury and other proliferating cell disorders regulated by hyaladherin and hyaluronans
US20030131364A1 (en) * 1999-04-27 2003-07-10 Karen Duff Method for producing transgenic animal models with modulated phenotype and animals produced therefrom
US20070160615A1 (en) * 1999-06-01 2007-07-12 Jun Tan Methods and compounds for disruption of CD40R/CD40L signaling in the treatment of Alzheimer's disease
US20050089939A1 (en) * 1999-06-01 2005-04-28 Jun Tan Assay for evaluating the therapeutic effectiveness of agents in reducing Alzheimer's disease pathology
US6787318B1 (en) 1999-06-01 2004-09-07 Roskamp Research Institute, Llc Assay for evaluating the therapeutic effectiveness of agents in reducing Alzheimer's disease pathology
US20060127366A1 (en) * 1999-06-25 2006-06-15 Mitrani Eduardo N Method and device for inducing biological processes by micro-organs
US20030086914A1 (en) * 1999-06-25 2003-05-08 Yissum Research Development Company Of The Hebrew University Of Jerusalem Method and device for inducing biological processes by micro-organs
US6875582B1 (en) 1999-08-19 2005-04-05 Omniscience Pharmaceuticals, Inc. Methods and targets of antibiotic resistance
US6998232B1 (en) 1999-09-27 2006-02-14 Quark Biotech, Inc. Methods of diagnosing bladder cancer
US7385106B2 (en) 2000-01-24 2008-06-10 Ramot At Tel Aviv University Ltd. Plants tolerant of environmental stress conditions, methods of generating same and novel polynucleotide sequence utilized thereby
US20030211490A1 (en) * 2000-01-24 2003-11-13 Hanan Stein Plants tolerant of environmental stress conditions, methods of generating same and novel polynucleotide sequence utilized thereby
US8088160B2 (en) 2000-07-20 2012-01-03 Multi-Gene Vascular Systems Ltd. (“MGVS”) Drug-eluting intravascular prostheses and methods of use
US20040078847A1 (en) * 2001-03-22 2004-04-22 Nitzan Paldi Method of enhancing entomophilous
EP1967525A2 (en) 2001-05-08 2008-09-10 Darwin Molecular Corporation A method for regulating immune function in primates using the foxp3 protein
US8178128B2 (en) 2001-12-05 2012-05-15 Yissum Research Development Company Of The Hebrew University Of Jerusalem Ltd. Nanoparticles containing polymeric nucleic acid homologs
US20060051426A1 (en) * 2001-12-05 2006-03-09 Gershon Golomb Nanoparticles containing polymeric nucleic acid homologs pharmaceutical composition and articles of manufacture containing same and methods of use thereof
EP2329814A1 (en) 2002-02-13 2011-06-08 Technion Research and Development Foundation, Ltd. Antibody having a T-cell receptor-like specificity, yet higher affinity, and the use of same in the detection and treatment of cancer
EP2072045A2 (en) 2002-02-13 2009-06-24 Technion Research and Development Foundation, Ltd. Antibody having a t-cell receptor-like specificity, yet higher affinity, and the use of same in the detection and treatment of cancer, viral infection and autoimmune disease
US20040005571A1 (en) * 2002-07-03 2004-01-08 Hawley R. Scott Axs gene and protein and methods related thereto
US20040146949A1 (en) * 2002-10-25 2004-07-29 Jun Tan Methods and compounds for disruption of CD40R/CD40L signaling in the treatment of alzheimer's disease
US20060206950A1 (en) * 2002-11-04 2006-09-14 Kaelin William G Jr In vivo imaging of e2f-fegulated bioluminescent proteins
US20050095240A1 (en) * 2002-11-22 2005-05-05 Medical College Of Georgia Research NaCT as a target for lifespan expansion and weight reduction
EP2338906A1 (en) 2003-06-16 2011-06-29 UCB Manufacturing, Inc. Compostion and methods for increasing bone mineralization
EP2341071A1 (en) 2003-06-16 2011-07-06 UCB Manufacturing, Inc. Compostion and methods for increasing bone mineralization
EP2526953A1 (en) 2003-07-15 2012-11-28 Bar-Ilan University Methods and pharmaceutical compositions for healing wounds
EP2540302A1 (en) 2003-07-15 2013-01-02 Bar-Ilan University Methods and pharmaceutical compositions for healing wounds
EP2540301A2 (en) 2003-07-15 2013-01-02 Bar-Ilan University Methods and pharmaceutical compositions for healing wounds
EP2526952A1 (en) 2003-07-15 2012-11-28 Bar-Ilan University Methods and pharmaceutical compositions for healing wounds
US7790673B2 (en) 2003-12-12 2010-09-07 New York University Methods and compositions relating to cystatin C
US20070032421A1 (en) * 2003-12-12 2007-02-08 Efrat Levy Methods and compositions relating to cystatin C
US20060019241A1 (en) * 2004-04-20 2006-01-26 Vadivel Ganapathy Na+ and CI-coupled transport system for endogenous opioid peptides
WO2007088418A1 (en) 2006-01-31 2007-08-09 Multi Gene Vascular Systems, Inc. Drug-eluting intravascular prostheses and methods of use
US20090017112A1 (en) * 2006-03-01 2009-01-15 Roskamp Research Llc Compounds for Inhibiting Beta-Amyloid Production
US8586024B2 (en) 2006-09-14 2013-11-19 Medgenics Medical Israel Ltd. Long lasting drug formulations
US8454948B2 (en) 2006-09-14 2013-06-04 Medgenics Medical Israel Ltd. Long lasting drug formulations
US8877175B2 (en) 2006-09-14 2014-11-04 Medgenics Medical Israel Ltd. Long lasting drug formulations
US9127084B2 (en) 2006-09-14 2015-09-08 Medgenics Medical Israel Ltd. Long lasting drug formulations
US9155749B2 (en) 2006-09-14 2015-10-13 Medgenics Medical Israel Ltd. Long lasting drug formulations
US9687564B2 (en) 2006-09-14 2017-06-27 Medgenics Medical Israel Ltd. Long lasting drug formulations
US20100119599A1 (en) * 2006-12-08 2010-05-13 Archer Pharmaceuticals, Inc. Polyhydroquinoline compounds and dihydropyridine compounds for inhibiting beta-amyloid production
US20080227692A1 (en) * 2007-03-16 2008-09-18 Moshe Flugelman Compositions and methods for treating ophthalmic disorders
WO2008152507A2 (en) 2007-03-16 2008-12-18 Multigene Vascular Systems, Inc. Compositions and methods for treating ophthalmic disorders
EP2514766A2 (en) 2007-03-29 2012-10-24 Technion Research & Development Foundation Ltd. Antibodies, methods and kits for diagnosing and treating melanoma
WO2008120202A2 (en) 2007-03-29 2008-10-09 Technion Research & Development Foundation Ltd. Antibodies, methods and kits for diagnosing and treating melanoma
WO2015059701A1 (en) 2013-10-24 2015-04-30 Medgenics Medical Israel Ltd. Micro-organs providing sustained delivery of a therapeutic polypeptide and methods of use thereof

Also Published As

Publication number Publication date
EP0289121B1 (en) 1995-12-27
EP0289121A2 (en) 1988-11-02
ATE132266T1 (en) 1996-01-15
DE3854823T2 (en) 1996-05-23
JP2618973B2 (en) 1997-06-11
JPS6427478A (en) 1989-01-30
DE3854823D1 (en) 1996-02-08
EP0289121A3 (en) 1990-06-06

Similar Documents

Publication Publication Date Title
US5347075A (en) Mutagenesis testing using transgenic non-human animals carrying test DNA sequences
US5955056A (en) Mutagenesis testing using transgenic non-human animals carrying test DNA sequences
Cockett et al. Polar overdominance at the ovine callipyge locus
EP0370813A2 (en) Rapid screening mutagenesis and teratogenesis assay
US5824287A (en) Mutagenesis testing using transgenic non-human animals carrying test DNA sequences
Bloom et al. Chromosomal localization of the major histocompatibility (B) complex (MHC) and its expression in chickens aneuploid for the major histocompatibility complex/ribosomal deoxyribonucleic acid microchromosome
US6221647B1 (en) Efficient construction of gene targeting using phage-plasmid recombination
WO1993015769A1 (en) Mutagenesis testing using transgenic non-human animals carrying test dna sequences
JPH0829093B2 (en) Method for rescue DNA and method for detecting mutation in marker gene
US5762908A (en) Process for detecting potential carcinogens
US20080260753A1 (en) Mouse Models of Crohn's Disease and a Method to Develop Specific Therapeutics
CA2079792A1 (en) Mutagenesis testing using transgenic non-human animals carrying test dna sequences
Guo mig-5, a gene that controls cell fate determination and cell migration in C. elegans, is a member of thedsh family
US6472583B1 (en) Plasmid-based mutation detection system in transgenic fish
WO1989009272A1 (en) A transgenic mouse for measurement and characterization of mutation induction in vivo
Oancea et al. An improved system of somatic cell molecular genetics for analyzing the requirements of Ig synthesis and function
JP3319602B2 (en) Methods for identifying lymphocytes having a mutagenic phenotype
WO1993017123A1 (en) Mutagenicity testing using reporter genes with modified methylation frequencies
JP3799445B2 (en) Transgenic rat for mutation detection, its production method and mutation test method using the same
Wagner Accessing novel developmental mechanisms in the mouse by gene trapping
JPH02145200A (en) Inspection for rapidly screening mutagenicity and teratogenicity
Thomson The developmental potential of androgenones, gynogenones, and parthenogenones
Snyder Isolation and characterization of second chromosomal mutagen-sensitive strains of Drosophila melanogaster.
Manolakou et al. Meeting Report: The Twelfth International Mouse Genome Conference
Demczuk et al. Genetic analysis of the maternal factors controlling the survival of trisomy 16 mouse fetuses

Legal Events

Date Code Title Description
AS Assignment

Owner name: STRATAGENE, CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:SORGE, JOSEPH A.;REEL/FRAME:006478/0325

Effective date: 19930401

STCF Information on status: patent grant

Free format text: PATENTED CASE

AS Assignment

Owner name: UNION BANK, CALIFORNIA

Free format text: SECURITY AGREEMENT;ASSIGNOR:STRATAGENE;REEL/FRAME:007779/0610

Effective date: 19951201

AS Assignment

Owner name: UNION BANK OF CALIFORNIA, N.A., CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:UNION BANK;REEL/FRAME:007991/0247

Effective date: 19960401

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

FPAY Fee payment

Year of fee payment: 4

FPAY Fee payment

Year of fee payment: 8

AS Assignment

Owner name: STRATAGENE CALIFORNIA, CALIFORNIA

Free format text: CHANGE OF NAME;ASSIGNOR:STRATAGENE;REEL/FRAME:016182/0616

Effective date: 20031209

AS Assignment

Owner name: STRATAGENE, CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:UNION BANK OF CALIFORNIA, N.A.;REEL/FRAME:014885/0317

Effective date: 20040115

FPAY Fee payment

Year of fee payment: 12

AS Assignment

Owner name: AGILENT TECHNOLOGIES, INC., COLORADO

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:STRATAGENE CALIFORNIA;REEL/FRAME:024630/0870

Effective date: 20100615